Apparatus for applying closure sheets to containers



J. STALLER Dec. 14, 1954 APPARATUS FOR APPLYING CLOSURESHEETS TOCONTAINERS 2 Shea s-Sheet 1 Filed May 17, 1950 J. STALLER Dec. 14, 1954APPARATUS FOR APPLYING CLOSURE SHEETS TO CONTAINERS 2 Sheets-Sheet .2

Filed May 17, 1950 INVENTOR.

United States Patent 'APPARATUS FOR APPLYING CLOSURE SHEETS TOCONTAINERS Jan Staller, Zurich-Erlenbach, Switzerland Application May-17, 1950, Serial No. 162,430

9 Claims. (Cl. 226-86) The present invention relates to an apparatus forsecuringa closure sheet across the mouth of a container, for instance abottle, the closure sheet having a concavoconvex shape having the convexside thereof directed toward the interior of the container.

The concavo-convex shape of the closure sheet is particularly suitablefor beer bottles or the like in which a considerable excess pressureexists inside the bottle.

It is an object of the present invention to provide an apparatus of thekind described which is suitable for securing closure sheets havingrelatively large tolerances in their dimensions.

It is another object of the present invention to provide an apparatuswhich can apply the closure sheet to mouths of containers havingdifferences in their shape, particularly such as are due to wear.

It is a further object of the present invention to avoid a flattening ofthe concavo-convex shape of the closure sheet during the securingthereof so that the latter is able to withstand a high internal pressuresuch as a pressure occurring in pasteurization of the bottle contents.

An apparatus according to the present invention comprises in combinationa casing having an open end portion for arranging therein the mouth ofthe container and a conical surface arranged on the inside of the casingadjoining the end portion, a plurality of members having conicallyshaped outer and inner surfaces, the outer surfaces of the membersslidably engaging the conical surface of the casing, the members beingadapted for bending the closure sheet into container-closing position, adriving element having a conical surface engaging the inner surfaces ofthe members so as to shift the same laterally toward the outside withrespect to the container, resilient means arranged in the upper portionof the casing between the driving element and the members, means forarranging the element for a limited radial displacement in the casing soas to allow a non-uniform arrangement of the members in accordance withirregularities of the mouth of the. container, and abutments connected,respectively, to the members and adapted to contact the concave side ofthe closure sheet opposite to the convex side thereof.

In a preferred embodiment of the present invention extensions arearranged, respectively, on the members in continuation to the conicallyshaped outer surfaces thereof so as to abut against a closure memberarranged on the mouth of the container and so as to substantiallyenclose the rim portion of the closure sheet, the extensions beingspaced apart from the rim portion of the closure sheet; and recesses arearranged in said members, respectively, adjoining the inner sides of theextensions, respectively, and adapted to receive the rim portion of theclosure sheet.

In a preferred embodiment of the present invention the abutments areintegral, respectively, with the conically shaped members.

According to a preferred embodiment of the present invention abutmentmeans are provided between the driving element and the casing permittingthe element to carry out a limited radial displacement in the casing soas to allow a non-uniform arrangement of the members in accordance withirregularities of the mouth of the container.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together 2,696,938 Patented Dec. 14, 1954- with additionalobjects and advantages thereof, will be best understood from thefollowing description of specific embodiments when read in connectionwith the accompanying drawings, in which:

Fig. 1 is a longitudinal cross-section through an apparatus according tothe present invention and the mouth of a bottle, the parts being shownbefore the securing of the closure sheet; and

Fig. 2 is a similar cross-section of the apparatus shown in Fig. l, theparts having the position after the securing of the closure sheet.

Fig. 3 is a fragmentary sectional view taken along the line 3--3 of Fig.1 in the direction of the arrows.

Referring now to the drawings, and first to Fig. 1 the mouth 22 of theneck 1 of a bottle or container is arranged at the lower end of thecasing 7, 8. The mouth 22 carries an elastically resilient sealingannulus 3 and an annular cap 2 preferably consisting of sheet metal andpermanently securing the annulus 3 to the mouth 22 of the neck 1 of thebottle. A concavo-convex closure sheet 4 is arranged across the mouth 22of the neck 1 of the bottle and has the convex side thereof directedtoward the interior of the bottle. The closure sheet 4 may consist ofmetal and has a marginal portion 23 and a rim portion 19. The marginalportion 23 establishes the connection between the concavo convex portionof the closure sheet 4 and the rim portion 19 and is before the securingof the closure sheet arranged in a substantially vertical position andin contact with the resilient annulus 3 whereas the rim portion 19 isarranged in a substantially horizontal position and in contact with thecap 2, as clearly shown in Fig. 1.

In order to secure the closure sheet to the bottle an apparatus is usedwhich comprises a casing having a longitudinal axis, a lower part 7 andan upper part 8. The lower part 7 has a lower open end portion 24 of asubstantially cylindrical shape for arranging therein the mouth 22 ofthe neck 1 of the bottle. Furthermore a conical surface 15 is arrangedon the inside of the lower part 7 of the casing adjoining the endportion 24 and located about the axis of the casing. Members 5 have partconically shaped outer and inner surfaces 25 and 26, respectively,forming parts of two cones located about the casing axis the outersurfaces 25 of the members 5 slidably engaging the conical surface 15 ofthe casing 7, 3 and members 5 being distributed about the casing axis.The members are provided at their lower end with lateral protuberances 6engaging the marginal portion 23 of the closure sheet 4. The partconically shaped inner surfaces 26 are in engagement with the conicalsurface 14 of a driving element 10 (Fig. 3). The part conical surfaces25 and 26 are preferably substantially parallel to each other.

The driving element 10 has a part at its upper end 20 enlarged to form aflange-like disk which is in contact with the surface 13 of the upperpart 8 of the casing which is arranged at right angles to the axis ofthe apparatus. The flange-like disc 20 can carry out limited radialdisplacements within the upper part 8 of the casing. A sleeve 11 havinga lateral flange 21 and enclosing the middle portion of the element 10rests on the upper end of the members 5' and resilient means includingthe sleeve 11 and a spring 12, is arranged between the member 5 and theflange-like disc 20 of the driving element 10, the spring 12 engagingflange 21 of sleeve 11.

The upper portion 8 of the casing carries a threaded portion 9 by whichthe apparatus may be connected to a part of a machine (not shown) whichmoves in vertical direction so that the casing 7, 8 can be lowered orraised with respect to the bottle. Abutments 16 are provided at thelower end of the members 5 and preferably made integral with them. Theabutments have a shape substantially corresponding to the concave sideof the closure sheet 4 so that they contact same.

Preferably extensions 17 are arranged, respectively, on the members 5 incontinuation to the part outer surfaces 25 thereof so as tosubstantially enclose the rim portion 19 of the closure sheet 4, theextensions 17 being spaced apart from the rim portion 19 of the closuresheet 4. Recesses 18 are provided in the members 5, respectively,adjoining the inner sides of the extensions 17 between the latter'andthe casing axis and having dimensions sufficient for accommodatingloosely therim portion 19 of the closure sheet 4.

The operation of this device is as follows:

In the position of the parts shown in Fig. 1 the casing 7, 8 is moveddownward so far that the closure sheet 4 is in contact with the annularcap 2 by means of the rim portion 19 and in contact with the sealingannulus 3 by means ofthe marginal portion 23, the'latter being in asubstantially vertical position. If the casing 7, 8 is moved furtherdownward into the position shown in Fig. 2, the driving element 10penetrates deeper into the space between themembers 5 and drives thesame radially outward with respect to the casing 7, 8 and the mouth 22of the neck ll of the bottle. During this movement the part conicallyshaped outer and inner surfaces 25 and 26 slide, respectively, on theconical surface of the casing 7, 8 and the' conical surface 14 of thedriving member 10. In consequence thereof, the protuberances 6 ofthemembers 5 exert a bending stress on the marginal portion 23 of theclosure sheet 4 so that it assumes the shapeshown in Fig. -2 in whichthe marginal portion 23 locks the closure sheet 4 against any ejectingaction of the pressure prevailing in the interior of the bottle. Sincethe main portion of the closure sheet 4 abuts against theabutments 16 itwill not be flattened during this operation. In consequence thereof theclosure sheet 4 is capable of withstanding internal pressures in' thebottle even after it has been secured to the mouth 22 of the neck 1 ofthe bottle.

The marginal portion 23 is lengthened in width during the operation justdescribed and the material for lengthen ing-the width of the marginalportion 23 cannot be provided by the concavo-convex main portion of theclosure sheet-4 since this portion abuts against the abutments 16. Itis, however, provided by the rim portion 19 of the closure sheet 4 whichis loosely accommodated within the recesses 18 of the members 5. Theloose accommodation of the rim portion involves the advantage that thematerial of the closure sheet is not unduly stressed during the securingoperation so that the closure sheet 4 will not show any cracks in therim portion'19 or the marginal portion 23. v

The members 5 are arranged so as to be resiliently supported in theaxial direction of the apparatus which fact has a particular importancein case of an irregularity of the mouth 22 or the annular cap 2 of thebottle. If, for instance, the end face of'the annular cap 2 being incontact with the extensions 17 is uneven, such unevenness being due to awrong mounting of the cap on the bottleor to wear or damage duringtransportation or use, the extensions '17 adjust themselves to differentlevels and adjust the members 5 at different levels along the conicalguiding surfaces 14 and 15 so that automatically each protuberance 6 isimparted the correct level with respect to the adjoining portion of themarginal portion 23 of the closure sheet 4, which will adapt itself tothe uneven shape of the end face of the cap 2. The accuracy of thisadaptation increases with the number of members 5 provided in the casing7, 8. If the axial independent resiliency of the members 5 were notprovided, the members would adjust themselves all at the same levelcorresponding to the highest point of the uneven face of the cap 2 andthe protuberances 6 would not be able to secure a complete'sealing ofthe closure sheet 4.

Also if the aperture of the annular cap 2 is eccentrically arranged withrespect to the perimeter of the annularcap 2 the device according to thepresent invention achieves a perfect sealing of the bottle since thedriving element 10 can adapt itself to any irregularities by means ofthe flange-like disc 29 thereof which abuts freely against the surface13 of the upper part 8 of the casing. The flange-like disc can carryout'limited radial displacements and even assume a slightly inclinedposition with respect to the surface 13 so that the driving element 10can adapt itself to all irregularities which arise in practice.

The abutments 16 need not be integral with the membersS but'could bemade as separate pieces which are radially slidable with respect to themembers 5.

It will be understood that each of the elements described above, or twoor more together, may also find a useful application in other types ofapparatuses for securing a closure sheet across the mouth of a containerdiffering from the types described above.

While I have illustrated and described the invention as-embodied inanapparatus for securing'a closure sheet across the mouth of a bottle, Ido not intend to be limited to the details shown, since variousmodifications and structural changes may be made without departing inany way from the spirit of my invention.

Without further analysis, the foregoing will so fully reveal the gist ofmy invention that others can by applying current knowledge readily adaptit for various applications Without omitting features that, from thestandpoint of prior art, fairly constitute essential characteristics ofthe generic or specific aspects of this invention and, therefore, suchadaptations should and are intended to be comprehended within themeaning and range of equivalence of the following claims.

What I claim as new and desire to secure by Letters Patent is:

1. An apparatus for securing a closure sheet across the mouth of acontainer, the closure sheet having a concave-convex shape having theconvex side thereof directed toward the interior of the container,comprising in combination, a casing having a longitudinal axis, an openend portion for arranging therein the mouth of the container and aconical surface arranged on the inside of said casingadjoining said endportion and located about said axis; a plurality of members distributedabout said axis and each provided with an outer and inner surfacerespectively forming parts of two cones located about said axis, saidouter surfaces of said members slidably engaging said conical surface ofsaid casing, said members being adapted to bend the closure sheet intocontainer-closing position; a driving element having a conical surfacelocated substantially about said axis and engaging said inner surfacesof said members for shifting the same laterally away from said axis;resilient means arranged in the upper portion of said casing between apart of said driving element and said members; means for arranging saidelement for a limited radial displacement in said casing so as to allowa non-uniform arrangement of said members in accordance withirregularities of the mouth of the container; abutments connected,respectively, to' said members at the lower ends thereof and adapted tocontact the concave side of the closure sheet opposite to the convexside thereof; extensions arranged, respectively, on said members incontinuation to said outer surfaces thereof so as to substantiallyenclose a rim portion of the closure sheet, said extensions being spacedapart from the rim portion of the closure sheet; and said members havingrecesses, respectively, each recess being arranged between saidextension and said abutment on each member and adapted to accommodateloosely the rim portion of the closure sheet.

2. An apparatus for securing a closure sheet across the mouth of acontainer, the closure sheet having a concavo-convex shape having theconvex side thereof directed toward the interior of the container, therim portion of the closure sheet being in contact with a closure memberarranged on the mouth of the container, comprising in combination, acasing having a longitudinal axis, an open end portion for arrangingtherein the mouth of the container and a conical surface arranged on theinside of said casing adjoining said end portion and located about saidaxis; a plurality of members distributed about said axis and eachprovided with an outer and inner surface respectively forming parts oftwo cones located about said axis, said outer surfaces of said membersslidably engaging said conical surface of said casing and said membersbeing adapted to bend the closure sheet into container-closing position;a driving element having a conical surface located substantially aboutsaid axis and engaging said inner surfaces of said members for shiftingthe same laterally away from said axis; resilient means arranged in theupper portion of said casing between a part of said driving element andsaid members; means for arranging said element for a limited radialdisplacement in said casing so as to allow a non-uniform arrangement ofsaid members inaccordance with irregularities of the mouth of thecontainer; abutments connected, respectively, to said members at thelower ends thereof and adapted to contact the concave side of theclosure sheet opposite to the convex side thereof; extensions arranged,respectively, on said members in continuation to said outer surfacesthereof so as to abut against the closure sheet arranged on the mouth ofthe container and so as to substantially enclose the rim portion of theclosure sheet, said extensions being spaced apart from the rim. portionof the closure sheet; and said members having recesses rerpectively,each recess being arranged between said extension and said abutment oneach member and adapted to accommodate loosely the rim portion of theclosure sheet.

3. An apparatus for securing a closure sheet across the mouth of acontainer, the closure sheet having a concavo-convex shape having theconvex side thereof directed toward the interior of the container, therim portion of the closure sheet being in contact with a closure memberarranged on the mouth of the container, comprising in combination, .acasing having a longitudinal axis, an open end portion for arrangingtherein the mouth of the container and a conical surface arranged on theinside of said casing adjoining said end portion and located about saidaxis; a plurality of members distributed about said axis and eachprovided with an outer and inner surface respectively forming parts oftwo cones located about said axis, said outer surfaces of said membersslidably engaging said conical surface of said casing and said membersbeing adapted to bend the closure sheet into container-closing position;a driving element having a conical surface located substantially aboutsaid axis and engaging said inner surfaces of said members for shiftingthe same laterally away from said axis; resilient means arranged in theupper portion of said casing between a part of said driving element andsaid members; means for arranging said element for a limited radialdisplacement in said casing so as to allow a non-uniform arrangement ofsaid members in accordance with irregularities of the mouth of thecontainer; abutments being integral, respectively, with said members andadapted to contact the concave side of the closure sheet opposite to theconvex side thereof; extensions arranged, respectively, on said membersin continuation to said outer surfaces there of so as to abut againstthe closure sheet arranged on the mouth of the container and so as tosubstantially enclose the rim portion of the closure sheet, saidextensions being spaced apart from the rim portion of the closure sheet;and said members having recesses, respectively, each recess beingarranged between said extension and said abutment on each member andadapted to accommodate loosely the rim portion of the closure sheet.

4. An apparatus for securing a closure sheet across the mouth of acontainer, the closure sheet having a concave-convex shape having theconvex side thereof directed toward the interior of the container,comprising in combination, a casing having a longitudinal axis, an openend portion for arranging therein the mouth of the container and aconical surface arranged on the inside of said casing adjoining said endportion and located about said axis; a plurality of members distributedabout said axis and each provided with an outer and inner surfacerespectively forming parts of two cones located I about said axis, saidouter surfaces of said members slidably engaging said conical surface ofsaid casing and said members'being adapted to bend the closure sheetinto container-closing position; a driving element having a conicalsurface located substantially about said axis and engaging said innersurfaces of said members for shifting the same laterally away from saidaxis; resflient means arranged in the upper portion of said casingbetween said members and a part of said driving element engaging saidcasing so that said element can carry out a limited radial displacementin said casing so as to allow a non-uniform arrangement of said membersin accordance with irregularities of the mouth of the container;abutments connected, respectively, to said members at the lower endsthereof and adapted to contact the concave side of the closure sheetopposite to the convex side thereof; extensions arranged, respectively,on said members in continuation to said outer surfaces thereof so as tosubstantially enclose a rim portion of the closure sheet, saidextensions being spaced apart from the rim portion of the closure sheet;and said members having recesses, respectively, each recess beingarranged between said extension and said abutment on each member andadapted to accommodate loosely the rim portion of the closure sheet.

5. An apparatus for securing a closure sheet across the mouth of acontainer, the closure sheet having a concavo-convex shape having theconvex side thereof directed toward the interior of the container, therim portion of the closure sheet being in contact with a closure memberarranged on the mouth of the container, comprising in combination, acasing having a longitudinal axis, an open end portion for arrangingtherein the mouth of the container and a conical surface arranged on theinside of said casing adjoining said end portion and located about saidaxis; a plurality of members distributed about said axis and eachprovided with an outer and inner surface respectively forming parts oftwo cones located about said axis, said outer surfaces of said membersslidably engaging said conical surface of said casing and said membersbeing adapted to bend the closure sheet into container-closing position;a driving element having a conical surface located substantially aboutsaid axis and engaging said inner surfaces of said members for shiftingthe same laterally away from said axis; resilient means arranged in theupper portion of said casing between said members and a part of saiddriving element engaging said casing so that said element can carry outa limited radial displacement in said casing so as to allow anon-uniform arrangement of said members in accordance withirregularities of the mouth of the container; abutments connected,respectively, to said members at the lower ends thereof and adapted tocontact the concave side of the closure sheet opposite to the convexside thereof; extensions arranged, respectively, on said members incontinuation to said part outer surfaces thereof so as to abut againstthe closure sheet arranged on the mouth of the container and so as tosubstantially enclose the rim portion of the closure sheet, saidextensions being spaced apart from the rim portion of the closure sheet;and said members having recesses, respectively, each recess beingarranged between said extension and said abutment on each member andadapted to accommodate loosely the rim portion of the closure sheet.

6. An apparatus for securing a closure sheet across the mouth of acontainer, the closure sheet having a concavo-convex shape having theconvex side thereof directed toward the interior of the container, therim portion of the closure sheet being in contact with a closure memberarranged on the mouth of the container, comprising in combination, acasing having a longitudinal axis, an open end portion for arrangingtherein the mouth of the container and a conical surface arranged on theinside of said casing adjoining said end portion and located about saidaxis; a plurality of members distributed about said axis and eachprovided with an outer and inner surface respectively forming parts oftwo cones located about said axis, said outer surfaces of said membersslidably engaging said conical surface of said casing and said membersbeing adapted to bend the closure sheet into container-closing position;a driving element having a conical surface located substantially aboutsaid axis and engaging said inner surfaces of said members for shiftingthe same laterally away from said axis; resilient means arranged in theupper portion of said casing between said members and a top flange ofsaid'driving element engaging said casing so that said element can carryout a limited radial displacement in said casing so as to allow anon-uniform arrangement of said members in accordance withirregularities of the mouth of the container; abutments being integral,respectively, with said members and adapted to contact the concave sideof the closure sheet opposite to the convex side thereof; extensionsarranged, respectively, on said members in continuation to said outersurfaces thereof so as to abut against the closure sheet arranged on themouth of the container and so as to substantially enclose the rimportion of the closure sheet, said extensions being spaced apart fromthe rim portion of the closure sheet; and said members having recesses,respectively, each recess being arranged between said extension and saidabutment on each member and adapted to accommodate loosely the rimportion of the closure sheet.

7. An apparatus for securing a closure sheet across the mouth of acontainer, the closure sheet having a concavo-convex shape having theconvex side thereof directed toward the interior of the container,comprising in combination, a casing having a longitudinal central axis,an open end portion for arranging therein the mouth of the container anda conical surface arranged on the inside of said casing adjoining saidend portions and located about said axis; a plurality of independentlymovable members distr-ibuted about said axis and each provided with anouter and inner surface respectively forming parts of two cones locatedabout said axis, said outer surfaces: of said :members' slidably,engaging, said conical surface ofsaid casing and said members beingadapted to .bendthe closure sheet into container-closing position;resilient means operatively connected to said members for sliding thesame independently along said conical surfaceof said casing toward saidopen end portion thereof and said axis; a conical driv-ing elementengaging said inner conical surfaces of said members for shifting thesame laterally away from said axis and for limiting the movement of saidmembers: toward said axis and open end ,portion of said casing; meansfor arranging said element for a limited radial displacement in saidcasing so as to allow a non-uniform arrangement of said members inaccordancewith irregularities of the mouth of the; container; and meansfor moving said casing and element along said axis with respect to saidmembers to move said members radially and outwardly with respect tosaidaxis.

8. An apparatus for securing a closure sheet across themouth of acontainer, the closure sheet having a concavo-convex shape having theconvex side thereof directed toward the interior of the container, therim portion of theclosure sheet being in contact with a closure memberarranged on the mouth of the container, comprising in combination, acasing having a longitudinal axis, an open end portion for arrangingtherein the mouth of the container and a conical surface arranged on theinside of said casing adjoining said end portion and located about saidaxis; a plurality of members distributed about said axis and eachprovided with an outer and inner surface respectively forming parts oftwo cones located about said axis, said outer surfaces of said membersslidably engaging said conical surface of said casing and said membersbeing adapted to bend the closure sheet into containerclosing position;a driving element having a conical surface located substantially aboutsaid axis and engaging said inner surfaces of said members for shiftingthe same laterally away from said axis; resilient means arranged in theupper portion of said casing between a part of said driving element andsaid members; means for arranging said element for a limited radialdisplacement in said casing so as to allow a non-uniform arrangement ofsaid members in accordance with irregularities of the mouth of thecontainer; abutments connected, respectively, to said members at thelower ends thereof and adapted to contact the concave side of theclosure sheet opposite to the convex side thereof; extensions arranged,respectively, on said members in continuation to said outer surfacesthereof so as to abut against the closure member arranged on the mouthof the container and so as to substantially enclose the rim portion ofthe closure sheet, said extensions being spaced apart from the rimportion of the closure sheet; and said members having recesses,respectively, each recess being arranged between said extension and saidabutment on each member and adapted to accommodate loosely the rimportion of the closure sheet, said abutments protruding beyond saidextensions and having protuberances adapted to exert a bending stress ona marginal portion of the closure sheet.

9.iAn apparatus for securing a closure sheet across the. mouth of acontainer, the, closure sheet having a concavo-convex shape having theconvex side thereof directed toward the interior of the container, therim portion of the closure sheet being in contact with a closure memberarranged on the mouth of the container, comprising in combination, acasing having a longitudinal axis, an open end portion for arrangingtherein the mouth of the container and a conical surface arranged on theinside of said casing adjoining said end portion and located about saidaxis; a plurality of members distributed about said axis and eachprovided with an outer and inner surface respectively forming parts oftwo cones located about said axis, said outer surfaces of said membersslidaoly engaging said conical surface of said casing and said membersbeing adapted to bend the closure sheet into containenclosing position;a driving element having a conical surface located substantially aboutsaid axis and engaging said inner surfaces of said members for shiftingthe same laterally away from said axis; resilient means arranged in theupper portion of said casing be tween a part of said driving element andsaid members; means for arranging said element for a limited radialdisplacement in said casing so as to allow a non-uniform arrangement ofsaid members in accordance with irregularities of the mouth of thecontainer; abutments being integral, respectively, with said members andadapted to contact the concave side of the closure sheet opposite to theconvex side thereof; extensions arranged, respectively, on said membersin continuation to said outer surfaces thereof so as to abut against theclosure sheet arranged on the mouth of the container and so as tosubstantially enclose the rim portion of, the closure sheet, saidextensions being spaced apart from the rim portion of the closure sheet;and said members having recesses, respectively, each recess beingarranged between said extension and said abutment on each member andadapted to accommodate loosely the rim portion of the closure sheet,said abutments protruding beyond said extensions and havingpro-tuberances adapted to exert a bending stress on the marginal portionof the closure sheet.

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